OFFSET
1,12
LINKS
Antti Karttunen, Table of n, a(n) for n = 1..20000
FORMULA
MATHEMATICA
a[n_] := If[n == 1, 1, Module[{f=FactorInteger[n]}, GCD[ Times@@ (First[#] ^(Last[#]-1)& /@ f), Times@@((#-1)& @@@ f)]]]; Array[a, 120] (* Amiram Eldar, Dec 05 2018 *)
PROG
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Dec 05 2018
STATUS
approved